Use of nanodispersions in cosmetic end formulations

ABSTRACT

A description is given of the use of a nanodispersion, which comprises  
     (a) a membrane-forming molecule,  
     (b) a coemulsifier and  
     (c) a lipophilic component,  
     in cosmetic end formulation, which nanodispersion is obtainable by  
     (α) mixing the components (a), (b) and (c) until a homogeneous clear liquid is obtained, and  
     (β) adding the liquid obtained in step (α) to the water phase of the cosmetic end formulations, steps (α) and (β) being carried out without any additional supply of energy.  
     The nanodispersions used according to this invention can be easily prepared and are suitable as carrier systems for a very wide range of cosmetic active agents and oil-soluble dyes.

[0001] The present invention relates to the use of specificnanodispersions in cosmetic end formulations, to cosmetic endformulations comprising said nanodispersions and to the differentcosmetic uses of these end formulations.

[0002] Cosmetic preparations comprising, in addition to the basicsubstances responsible for forming the cosmetic formulations, otherfunctional active agents. These are added to the cosmetic baseformulations and are used, for example, for treatment, protection,colouring, cleansing, disinfection, for moisturising skin and forregenerating and activating skin or hair.

[0003] In order for these substances to have an effect at the desiredsite, they must be transported to the respective site, for example tothe skin surface, mucosae, nails, dental enamel or hair, but also to theepidermal and dermal areas of the skin, by means of so-called carrierand transport vehicles (carrier systems). To this purpose, many cosmeticactive agents, for example water-soluble vitamins, the amino acid groupor the water-soluble melanines, are encapsulated in liposomes. Owing tothe properties of the liposomes, lipophilic substances can beencapsulated only in minor amounts in the lipophilic areas of theliposome membrane. For this reason, so-called nanoemulsions, also callednanoparticles, are used for such compounds, e.g. fat-soluble vitamins.

[0004] Owing to the physical and chemical properties of the membranesand the membrane-forming molecules, the use of said carrier systems inconventional cosmetic formulations is severely limited.

[0005] Conventionally structured membranes are highly susceptible toamphiphilic substances, such as ionogenic or non-ionogenic emulsifiers,fatty amines, amphoteric emulsifiers, detergent surfactants, thickenersor preservatives which form the basis for many cosmetic preparations orwhich are present as so-called active agents or excipients in cosmeticend formulations. The structure of the membranes changes in the presenceof such substances, which may result in the destruction of the addedcarrier system during preparation.

[0006] Customary membranes are also exposed to the attack of acids andbases. Thus, it is required, for example, that carrier systemscontaining phospholipids can only be used in the range of the so-calledpH optimum of about pH 6.5. Lowering or raising of the pH results in thehydrolysis of the membrane-forming molecules.

[0007] Surprisingly, it has now been found that nanodispersions ofsuitable composition can, in the presence of amphiphilic substances, beincorporated into cosmetic end formulations over a wide pH range in verysimple manner while retaining their morphological and physicochemicalproperties.

[0008] Accordingly, this invention relates to the use of ananodispersion, which comprises

[0009] (a) a membrane-forming molecule,

[0010] (b) a coemulsifier and

[0011] (c) a lipophilic component,

[0012] in cosmetic end formulations, the nanodispersion being obtainableby

[0013] (α) mixing the components (a), (b) and (c) until a homogeneousclear liquid is obtained (so-called nanodispersion prephase), and

[0014] (β) adding the liquid obtained in step (α) to the water phase ofthe cosmetic end formulations, wherein steps (α) and (β)are carried outwithout any additional supply of energy.

[0015] Step (α) is usually carried out at room temperature, wherenecessary with heating and under normal pressure conditions. Mixing iscarried out using standard stirring apparatus, for example propeller,angled paddle or magnetic agitators, and without using any specialmechanical stirring aids.

[0016] Components (a), (b) and (c) (=step (α)) are mixed in anhydrousmedium, i.e. it is not necessary to add any water.

[0017] Step (β) is carried out by adding the liquid obtained in step(α), the nanodispersion prephase, to the water phase of the cosmetic endformulations. The particular choice of components (a), (b) and (c)results directly in ultrafine, monodisperse nanodispersions. In thiscase it is possible to forego homogenisation via nozzle, rotor-stator orultrasound homogenisers, which is usually carried out to convertcoarsely disperse or at least heterodisperse systems to finemonodisperse systems. Step (β) is thus characterised by the absence ofhigh shear or cavitation forces. Step (β) is usually carried out at roomtemperature, which is the range of the respective oil/water phaseinversion temperature (PIT).

[0018] The nanodispersions characterised by the process steps (α) and(β) contain particles having an average diameter of <50 nm, typically ofless than 30 nm. The distribution is monodisperse and correspons to aGaussian distribution.

[0019] According to this invention, it is preferred to use ananodispersion which contains,

[0020] (a) as membrane-forming molecules, substances which are suitablefor forming so-called bilayers,

[0021] (b) as coemulsifiers, substances which preferably form O/Wstructures and,

[0022] (c) as lipophilic component, a functional lipophilic active agentcustomarily used in cosmetics.

[0023] The nanodispersion preferably contains as component (a) aphospholipid, a hydrated or partially hydrated phospholipid, alysophospholipid, a ceramide, or mixtures of these compounds.

[0024] A very particularly preferred phospholipid is that of formula

[0025] wherein

[0026] R₁ is C₁₀-C₂₀acyl;

[0027] R₂ is hydrogen or C₁₀-C₂₀acyl

[0028] R₃ is hydrogen, 2-trimethylamino-1-ethyl, 2-amino-1-ethyl;C₁-C₅alkyl which is unsubstituted or substituted by one or severalcarboxy, hydroxy or amino groups; the inositol or glyceryl group;

[0029] or salts of these compounds.

[0030] C₁₀-C₂₀Acyl is preferably straight-chain C₁₀-C₂₀alkanoylcontaining an even number of carbon atoms and straight-chainC₁₀-C₂₀alkenoyl containing a double bond and an even number of carbonatoms.

[0031] Straight-chain C₁₀-C₂₀alkanoyl containing an even number ofcarbon atoms is, for example, n-dodecanoyl, n-tetradecanoyl,n-hexadecanoyl or n-octadecanoyl.

[0032] Straight-chain C₁₀-C₂₀alkenoyl containing a double bond and aneven number of carbon atoms is, for example, 6-cis- or 6-trans-, 9-cis-or 9-trans-dodecenoyl, -tetradecenoyl, -hexadecenoyl, -octadecenoyl or-eicosenoyl, preferably 9-cis-octa-decenoyl (oleoyl), and also9,12-cis-octadecadienoyl or 9,12,15-cis-octadecatrienoyl.

[0033] A phospholipid of formula (1), wherein R₃ is2-trimethylamino-1-ethyl, is referred to by the trivial name lecithin,and a phospholipid of formula (1), wherein R₃ is 2-amino-1-ethyl, by thetrivial name cephalin. Suitable are, for example, naturally occurringcephalin or lecithin, e.g. cephalin or lecithin from soybeans or chickeneggs with different or identical acyl groups, or mixtures thereof.

[0034] The phospholipid of formula (1) may also be of synthetic origin.The expression “synthetic phospholipid” is used to define phospholipidshaving uniform composition with respect to R₁ and R₂. Such syntheticphospholipids are preferably the lecithins and cephalins defined above,wherein the acyl groups R₁ and R₂ have a defined structure and which arederived from a defined fatty acid having a degree of purity greater thanabout 95%. R₁ and R₂ may be identical or different and unsaturated orsaturated. Preferably, R₁ is saturated, for example n-hexadecanoyl, andR₂ is unsaturated, for example 9-cis-octadecenoyl (oleoyl).

[0035] The expression “naturally occurring” phospholipid defines aphospholipid that does not have a uniform composition with respect to R₁and R₂. Such natural phospholipids are likewise lecithins and cephalins,wherein the acyl groups R₁ and R₂ are derived from naturally occurringfatty acid mixtures.

[0036] The requirement “substantially pure” phospholipid of formula (1)defines a degree of purity of more than 90% by weight, preferably ofmore than 95% by weight of the phospholipid of formula (1), which can bedemonstrated by means of suitable determination methods, for example bypaper chromatography, thin-layer chromatography, by HPLC or by means ofenzymatic colour testing.

[0037] In a phospholipid of formula (1), R₃ defined as C₁-C₄alkyl is,for example, methyl or ethyl. Methyl is preferred.

[0038] R₃ defined as C₁-C₅alkyl substituted by one or several carboxy,hydroxy or amino groups is, for example, 2-hydroxyethyl,2,3-dihydroxy-n-propyl, carboxymethyl, 1- or 2-carboxyethyl,dicarboxymethyl, 2-carboxy-2-hydroxyethyl or3-carboxy-2,3-dihydroxy-n-propyl, 3-amino-3-carboxy-n-propyl or2-amino-2-carboxy-n-propyl, preferably 2-amino-2-carboxyethyl.

[0039] Phospholipids of formula (1) containing these groups can bepresent in salt form, for example as sodium or potassium salt.

[0040] Phospholipids of formula (1), wherein R₃ is the inositol orglyceryl group, are known by the names phosphatidylinositol andphosphatidylglycerol.

[0041] The acyl radicals in the phospholipids of formula (1) are alsocustomarily known by the names given in brackets:

[0042] 9-cis-dodecenoyl (lauroleoyl), 9-cis-tetradecenoyl(myristoleoyl), 9-cis-hexadecenoyl (palmitoleoyl), 6-cis-octadecenoyl(petroseloyl), 6-trans-octadecenoyl (petroselaidoyl), 9-cis-octadecenoyl(oleoyl), 9-trans-octadecenoyl (elaidoyl), 9,12-cis-octadecadienoyl(linoleoyl), 9,12,15-cis-octadecatrienoyl (linolenoyl),11-cis-octadecenoyl (vaccenoyl), 9-cis-eicosenoyl (gadoleoyl),5,8,11,14-cis-eicosatetraenoyl (arachidonoyl), n-dodecanoyl (lauroyl),n-tetradecanoyl (myristoyl), n-hexadecanoyl (palmitoyl), n-octadecanoyl(stearoyl), n-eicosanoyl (arachidoyl), n-docosanoyl (behenoyl),n-tetracosanoyl (lignoceroyl).

[0043] A salt of the phospholipid of formula (1) is preferablycosmetically acceptable. Salts are defined by the existence ofsalt-forming groups in the substituent R₃ and by the free hydroxyl groupat the phosphorus atom. The formation of internal salts is alsopossible. Alkali metal salts, especially the sodium salt, are preferred.

[0044] In a particularly preferred embodiment of this invention,purified lecithin from soybeans of the quality LIPOID S 100 or S 75, ora lecithin defined in the monograph USP23/NF 18, is used.

[0045] Component (a) is preferably used in a concentration of about 0.1to 30% by weight, based on the total weight of the components (a), (b)and (c).

[0046] Component (b) is preferably an emulsifier or emulsifier mixturesforming the preferred O/W structures.

[0047] Especially preferred emulsifiers are

[0048] alkali, ammonium and amine salts of fatty acids. Examples of suchsalts are the lithium, sodium, potassium, ammonium, triethylamine,ethanolamine, diethanolamine or triethanolamine salts. It is preferredto use the sodium, potassium or ammonium (NR1R2R3) salts, wherein R₁, R₁and R₁ are each independently of one another hydrogen, C₁-C₄alkyl orC₁-C₄hydroxyalkyl.

[0049] saturated and unsaturated alkyl sulfates, such as sodiumdocecylsulfate and alkanesulfonates such as sodium dodecanesulfonate;

[0050] salts of colic acid, such as sodium cholate, sodium glycocholateand sodium taurocholate;

[0051] invert soaps (quats), such as zetylpyridinium chloride;

[0052] partial fatty acid esters of sorbitan, such as sorbitanmonolaurate;

[0053] sugar esters of fatty acids, such as sucrose monolaurate;

[0054] alkylglucosides, such as n-octylglucoside or n-dodecylglucoside;

[0055] alkylmaltosides, such as n-dodecylmaltoside;

[0056] fatty acid partial glycerides, such as lauric acid monoglyceride;

[0057] C₈-C₁₈betaines, C₈-C₂₄alkylamido-C₁-C₄alkylenebetaines andC₈-C₁₈sulfobetaines;

[0058] proteins, such as casein;

[0059] polyglycerol esters of fatty acids;

[0060] propylene glycol esters of fatty acids;

[0061] lactates of fatty acids, such as sodium stearoyllactyl-2-lactate;

[0062] fatty alcohol phosphorates.

[0063] Emulsifiers of the polyoxyethylene type are very particularlypreferred. Examples of such emulsifiers are:

[0064] polyethoxylated sorbitan fatty acid esters, such as polysorbate80;

[0065] polyethoxylated fatty alcohols, such as oleth-20;

[0066] polyethoxylated fatty acids, such as polyoxyl 20 stearate;

[0067] polyethoxylated vitamin E derivatives, such as vitamin Epolyethylene glycol 1000 succinate;

[0068] polyethoxylated lanoline and lanoline derivatives, such aslaneth-20;

[0069] polyethoxylated fatty acid partial glycerides, such as diethyleneglycol monostearate;

[0070] polyethoxylated alkylphenols, such as ethylphenolpoly(ethyleneglycol ether)11;

[0071] sulfuric acid semiester polyethoxylated fatty alcohols and theirsalts, such as C₁₂-C₁₄-fatty alcohol ether sulfate-2 EO-sodium salt;

[0072] polyethoxylated fatty amines and fatty acid amides;

[0073] polyethoxylated carbon hydrates

[0074] block polymers of ethylene oxide and propylene oxide, such aspoloxamer 188.

[0075] The nanodispersion preferably contains as component (b) at leastone emulsifier of the polyoxyethylene type, and very particularlypreferably an emulsifier of the polyoxyethylene type, or a mixture ofthese substances.

[0076] Component (b) is present in the nanodispersion used according tothis invention in a concentration of about 1 to about 50% by weight,based on the total weight of components (a), (b) and (c).

[0077] Component (c) is preferably a natural or synthetic or a partiallysynthetic di- or triglyceride, a mineral oil, silicone oil, wax, fattyalcohol, guerbet alcohol or the ester thereof, a lipophilic functionalcosmetic active agent including sunscreens, or a mixture of thesesubstances.

[0078] Component (c) is particularly preferably a sunscreen or afat-soluble vitamin.

[0079] An active agent, active agent composition or active agent extractsuitable for skin cosmetics is an ingredient or a mixture of ingredientswhich is approved for dermal or topic administration.

[0080] Examples to be listed are:

[0081] active agents which have cleansing action on the skin surface andhair. These include all those substances which are used for cleansingthe skin, for example oils, soaps, syndets and solid substances;

[0082] active agents having a deodorising and antiperspirant action:these include antiperspirants based on aluminium or zinc salts,deodorants containing bactericidal or bacteriostatic deodorisingsubstances, for example triclosan, hexachlorophene, alcohols andcationic substances, for example quaternary ammonium salts and smellabsorbers, for example ®Grillocin (combination of zinc rizinoleate anddifferent additives) or triethylcitrates, optionally in combination withan antioxidant, such as butylhydroxytoluene), or ion exchange resins;

[0083] active agents offering protection against sunlight (UV filters):suitable active agents are filter substances (sunscreens) which canabsorb the UV radiation from sunlight and convert it into heat.Depending on the desired effect, the following sunscreens are preferred:sunscreens which selectively absorb energy-rich, sunburning UV radiationin the range from about 280 to 315 nm (UV-B absorbers) and whichtransmit the longwave range from about 315 to 400 nm (UV-A range), andsunscreens which only absorb the longwave radiation of the UV-A rangefrom 315 to 400 nm (UV-A absorbers).

[0084] Suitable sunscreens are, for example, organic UV absorbers fromthe class of the p-aminobenzoic acid derivatives, salicylic acidderivatives, benzophenone derivatives, dibenzoylmethane derivatives,diphenylacrylate derivatives, benzofuran derivatives, polymeric UVabsorbers containing one or more than one silicium-organic radical,cinnamic acid derivatives, camphor derivatives, trianilino-s-triazinederivatives, phenylbenzimidazolesulfonic acid and the salts thereof,menthylanthranilates, benzotriazole derivatives, and/or an inorganicmicropigment selected from the group consisting of TiO₂, zinc oxide ormica encapsulated with aluminium oxide or silicium dioxide.

[0085] Examples of p-aminobenzoic acid derivative compounds are:

[0086] 4-aminobenzoic acid (PABA); ethyidihydroxypropyl-PABA of formula

[0087]  wherein m, n and x have the same meaning and each is at most 25;octyldimethyl PABA of formula

[0088] Examples of salicylic acid derivative compounds are:

[0089] Homomenthylsalicylate of formula

[0090] Examples of benzophenone derivative compounds are:

[0091] benzophenone-3-(2-hydroxy-4-methoxybenzophenone),benzophenone-4-(2-hydroxy-4-methoxybenzophenone-5-sulfonic acid) orbenzophenone-8-(2,2′-dihydroxy-4-methoxybenzophenone).

[0092] Examples of dibenzoylmethane derivative compounds are:

[0093]butylmethoxydibenzoylmethane-[1-(4-tert-butyl)-3-(4-methoxyphenyl)propane-1,3-dione].

[0094] Examples of diphenylacrylate derivative compounds are:

[0095] octocrylene(2-ethylhexyl-2-cyano-3,3′-diphenylacrylate) oretocrylene(ethyl-2-cyano-3,3′-diphenylacrylate).

[0096] Examples of benzofuran derivative compounds are:

[0097] 3-(benzofuranyl)-2-cyanoacrylate,2-(2-benzofuranyl)-5-tert-butylbenzoxazole or2-(p-aminophenyl)benzofuran and, in particular, the compound of formula

[0098] Examples of polymeric UV absorber compounds containing one ormore than one silicium-organic radical are:

[0099] benzylidenemalonate derivatives, in particular the compound offormula

[0100] wherein

[0101] R₂₄ is hydrogen or O—Me, and

[0102] r is approximately 7; the compound of formula

[0103] Examples of cinnamate compounds are:

[0104] octylmethoxycinnamate (4-methoxycinnamic acid-2-ethylhexylester), diethanolaminemethoxycinnamate (diethanolamine salt of4-methoxycinnamic acid), isoamyl-p-methoxycinnamate (4-ethoxycinnamicacid-2-isoamyl ester), 2,5-diisopropylmethylcinnamate or a cinnamic acidamido derivative.

[0105] Examples of camphor derivative compounds are:

[0106] 4-methylbenzylidene camphor[3-(4′-methyl)benzylidenebornan-2-one], 3-benzylidenecamphor(3-benzylidenebornan-2-one), polyacrylamidomethylbenzylidenecamphor{N-[2(and 4)-2-oxyborn-3-ylidenemethyl)benzyl]acrylamide polymer},trimoniumbenzylidenecamphorsulfate-[3-(4′-trimethylammonium)benzylidenebornan-2-onemethylsulfate],terephthalydenedicamphorsulfonic acid{3,3′-(1,4-phenylenedimethine)-bis-(7,7-dimethyl-2-oxobicyclo-[2.2.1]heptane-1-methanesulfonicacid} or the salts thereof, or benzylidenecamphorsulfonic acid[3-(4′-sulfo)benzylidenebornan-2-one] or the salts thereof.

[0107] Examples of trianilino-s-triazine derivative compounds are:

[0108]octyltriazine-[2,4,6-trianilino-(p-carbo-2′-ethyl-1′-oxy)-1,3,5-triazineand the trianilino-s-triazine derivatives described in U.S. Pat. No.5,332,568, U.S. Pat No. 5,252,323, WO 93/17002 and WO 97/03642 andEP-A-0,517,104; the resorcinyltriazines described in EP-A-0,775,698, inparticular the compounds of formula

[0109] Examples of benzotriazole compounds are:

[0110] 2-(2-hydroxy-5-methylphenyl)benzotriazole; the benzotriazolecompounds disclosed in EP-A-0,746,305, in particular the compound

[0111]  wherein T₂ is hydrogen; or C₁-C₈alkyl;

[0112] insect repellents: repellents are compositions which shouldprevent insects from touching the skin and getting active there. Theyrepel the insects and slowly evaporate. The most frequently usedrepellent is dethyltoluamide (DEET). Other customary repellents are tobe found in “W. Raab and U. Kindl, “Pflegekosmetik”,Gustav-Fischer-Verlag Stuttgart/New York,1991, p.161;

[0113] active agents protecting against chemical and mechanical attack:these include all those substances which form a barrier between the skinand the outer noxa, such as paraffin oils, silicone oils, vegetableoils, PCL products and lanoline as protection against aqueous solutions,film formers, such as sodium alginate, triethanolamine alginate,polyacrylates, polyvinyl alcohol or cellulose ethers against the actionof organic solvents, or substances based on mineral oils, vegetable oilsor silicone oils as “lubricants” against high mechanical stresses of theskin;

[0114] moisturising substances: the following substances are used asmoisturisers: sodium lactate, urea, alcohols, sorbitol, glycerol,propylene glycol, collagen, elastin or hyaluronic acid;

[0115] active agents having ceratoplastic activity: benzoylperoxide,retinic acid, colloidal sulfur and resorcinol;

[0116] antimicrobial agents, for example triclosan or quaternaryammonium compounds;

[0117] dermally applicable oily or oil-soluble vitamins or vitaminderivatives: e.g. vitamin A (getinol in the form of the free acid or itsderivatives), panthenol, pantothenic acid, folic acid, and combinationsthereof, vitamin E (tocopherol), F; essential fatty acids; orniacin-amide (nicotinic acid amide);

[0118] vitamin-based placenta extracts: active agent compositions mainlywith vitamin A, C, E, B₂₁ B₁₂, folic acid and biotin, amino acids andenzymes and also compounds of the trace elements magnesium, silicium,phosphorus, calcium, manganese, iron or copper.

[0119] skin repair complexes: obtainable from inactivated anddesintegrated cultures of bacteria of the bifidus group;

[0120] plants and plant extracts: for example arnica, aloe, beardlichen, ivy, nettle, ginseng, henna, camomile, calendula, rosemary,sage, equisetum or thyme;

[0121] animal extracts: for example royal jelly, propolis, proteins orthymus extracts;

[0122] dermally applicable cosmetic oils: neutral oils of the miglyol812 type, apricot kernel oil, avocado oil, babassu oil, cottonseed oil,borage oil, thistle oil, groundnut oil, gamma-oryzanol, rosehip seedoil, hemp oil, hazelnut oil, currant seed oil, jojoba oil, cherrystoneoil, salmon oil, linseed oil, corn oil, macadamia nut oil, almond oil,evening primrose oil, mink oil, olive oil, pecan nut oil, peach kerneloil, pistachio nut oil, rapeseed oil, rice germ oil, castor oil,safflower oil, sesame oil, soybean oil, sunflower oil, tea tree oil,grapeseed oil or wheat germ oil.

[0123] Component (c) is present in the nanodispersions used according tothis invention in a concentration of preferably 0.1 to 80% by weight,based on the total weight of components (a), (b) and (c).

[0124] Components (a), (b) and (c) can be present in the nanodispersionsused according to this invention as individual compounds or as mixturesof several different individual components.

[0125] At least one component (a), (b) or (c) in the nanodispersioncomposition is usually a functional active agent used in cosmetics fortreating or protecting the skin, mucosae and hair.

[0126] The nanodispersion used according to this invention optionallycomprises as facultative component (d) a solubilising agent, preferablya C₂-C₈alcohol, such as ethanol or propylene glycol.

[0127] A nanodispersion containing the components (a), (b), (c) andoptionally (d) is distinguished by favourable phase properties of thesolubilised functional cosmetic agent. Thus if there is opalescence andtransparency in incident light, only a very slight turbidity shows thatthe dispersion is physically still different from the ideal state of agenuine molecular solution. Electron microscopic images show that apopulation of more than 98% is present in a Gaussian distribution as asuspension of particles (nanoparticles) having a particle size of lessthan about 50 nm, typically of less than about 30 nm. However, thesedistinctions from a genuine solution can be tolerated because of theparticularly good homogeneity properties of the dispersion which can beevidenced, for example, by a surprisingly high storage stability, e.g.no separation after storing for several months at temperatures of up toroom temperature (stability to be expected by extrapolation: more thantwo years).

[0128] Laser light scattering measurements and electron microscopicanalysis (Cryo-TEM) confirm the very small size and excellenthomogeneity of the nanoparticles present in the nanodispersion.

[0129] Another advantage of the nanodispersions used according to thisinvention is that they are easy to prepare.

[0130] The nanodispersions characterised by claim 1 are used accordingto this invention for cosmetic end formulations.

[0131] This invention also relates to the so-called nanodispersionprephase characterised in step (α), which is obtainable by mixing thecomponents

[0132] (a) membrane-forming molecules,

[0133] (b) coemulsifier,

[0134] (c) lipophilic component and, optionally,

[0135] (d) a C₂-C₈alcohol, preferably propylene glycol and, morepreferably, ethanol until a homogeneous clear liquid is obtained, mixingbeing carried out in anhydrous medium.

[0136] These nanodispersion prephases can likewise be directly used inaccordance with this invention for cosmetic end formulations.

[0137] Cosmetic end formulations include a very wide range of cosmeticproducts. Suitable products are, for example, especially the following:

[0138] skin-care products, for example skin washing and cleansingproducts in the form of bars of soap or liquid soaps, syndets or washingpastes,

[0139] bath products, for example liquid (foam baths, milks, showerproducts) or solid bath products, such as bath pearls and bath salts;

[0140] skin-care products, such as skin emulsions, multiple emulsions orskin oils;

[0141] decorative body-care products, for example face make-ups in theform of day or powder creams, face powders (lose and compressed), rougeor cream make-ups, eye-care products, for example eye shadow products,mascara, eyeliners, eye creams or eye-fix creams; lip-care products, forexample lipstick, lip gloss, lip liner, nail-care products, such as nailvarnish, nail varnish remover, nail hardeners or cuticle removers;

[0142] feminine hygiene products, such as feminine hygiene washinglotions or sprays;

[0143] foot-care products, for example foot baths, foot powders, foodcreams or foot balms, special deodorants and antiperspirants or productsfor scrubbing off callouses;

[0144] sunscreens, such as sun milks, lotions, creams, oils, sunblockersor tropicals, pre-sun products or after-sun products;

[0145] suntanning products, for example self-tanning creams;

[0146] depigmenting products, for example products for bleaching orlightening skin;

[0147] insect repellents, for example insect oils, lotions, sprays orsticks;

[0148] deodorants, for example deodorant sprays, non-aerosol sprays,deodorant gels, sticks or roll-ons;

[0149] antiperspirants, for example antiperspirant sticks, creams orroll-ons;

[0150] products for cleansing and treating impure skin, for examplesyndets (solid or liquid), peeling or scrubbing products or peelingmasks;

[0151] chemical depilatory products, for example depilatory powders,liquid depilatory products, creamy or pasty depilatory products,depilatory gels or aerosol foams;

[0152] shaving products, for example shaving soap, foaming shavingcreams, non-foaming shaving creams, shaving foams and gels, preshavingproducts for dry shaving, aftershaves or aftershave lotions;

[0153] scents, for example perfumes (Eau de Cologne, Eau de Toilette,Eau de Parfum, Parfum de Toilette, perfume), perfume oils or perfumecreams;

[0154] products for oral and dental hygiene as well as for dentures, forexample toothpastes, tooth gels, tooth powders, mouth-wash concentrates,anti-plaque mouth-washes, denture cleaning products or denture adhesionproducts;

[0155] cosmetic formulations for hair treatment, for example hair washesin the form of shampoos, hair conditioners, hair-care products, forexample pretreatment products, hair tonics, hair styling creams andgels, pomades, hair rinses, deep conditioning treatments, intensive haircare treatments, hair setting products, for example waving agents forperms (hot wave, mild wave, cold wave), hair straightening products,liquid hair fixatives, hair foams, hair sprays, bleaching agents, forexample hydrogen peroxide solutions, bleaching shampoos, bleachingcreams, bleaching powders, bleaching pastes or oils, temporary,semitemporary or permanent hair dyes, products containing self-oxidisingdyes, or natural hair dyes, such as henna or camomile.

[0156] The end formulations listed above can be in a very wide range offorms of presentation, for example

[0157] in the form of liquid formulations as an O/W emulsion,

[0158] in the form of a gel,

[0159] in the form of an oil, cream, milk or lotion,

[0160] in the form of a powder, lacquer, pellets or make-up,

[0161] in the form of a stick,

[0162] in the form of a spray (spray with propellant or non-aerosolspray) or an aerosol,

[0163] in the form of a foam, or

[0164] in the form of a paste.

[0165] The liquid and semisolid forms of presentation in this casecontain the nanodispersion with the components (a), (b) and (c) in theaqueous phase, and one or several of the above functional cosmeticactive agent(s). Solid forms of presentation contain the nanodispersionin the dehydrated form, the dehydration of the nanodispersion usuallybeing carried out by freeze-drying or spray-drying in the presence ofcustomary auxiliaries. For some end formulations it is advantageous toreplace the nanodispersion with the corresponding nanodispersionsprephase.

[0166] Emulsions are heterogeneous systems consisting of two liquids(phases) which are not, or only partly, miscible with each other. Onephase is present in the form of droplets (dispersed or inner phase),whereas the other forms a continuous phase as a liquid. In the case ofan O/W emulsion, which is basically characterised by water, oil dropletsare finely dispersed in water.

[0167] Creams are usually spreadable in the temperature range from roomto skin temperature, whereas lotions or milks tend to be pourable.

[0168] Gels are semisolid, more or less transparent systems in which theso-called gel former forms a three-dimensional network in which a liquidis immobilised. The clear to opaque hydrogels consist primarily ofwater, water-soluble substances and thickeners or gel formers. If lipidsare additionally incorporated, the slightly creamy-lookinghydrodispersion gels are obtained. In contrast, the oleogels are free ofwater and contain lipids as liquid components.

[0169] The cosmetic end formulation containing one or several of theabove ingredients which may be in the form of the above-mentioned formsof presentation, contains the nanodispersion used according to thisinvention preferably in a concentration of 0.01 to 100, preferably of0.01 to 20.0, more preferably of 0.05 to 5% by weight.

[0170] These end formulations are another subject matter of thisinvention.

[0171] The end formulations in this case contain the nanodispersion intheir aqueous phase in a concentration of 0.01 to 20.0, preferably of0.05 to 10 and, more preferably of 0.1 to 5% by weight.

[0172] The end formulation used according to this invention can alsocontain other components, for example emollients, emulsion stabilisers,skin moisturisers, suntanning accelerators, thickeners, such asxanthane, moisture retention agents, such as glycerol, preservatives,such as parabene, antioxidants, as well as fragrances and colourants.

[0173] The basic formulations for the cosmetic end formulationsaccording to Examples 14 to 21 are prepared in accordance with theinstructions in “Kosmetik; Entwicklung, Herstellung und Anwendungkosmetischer Mittel” (Ed.: W. Umbach, Georg Thieme Verlag Stuttgart, NewYork) and with the documentations from “DGK Fortbildungskurs 1998,Entwicklung moderner Hautpflegemittel”.

[0174] The end formulations are prepared by the customary known methods,some of which are described in the above literature. In the case ofliquid and semisolid end formulations, the nanodispersions are alwaysincorporated into the aqueous phase of the end formulations. To thispurpose, they are taken up in a small proportion of the aqueous phaseand are added, as active agent phase, as last phase during thepreparation of a formulation at about 20 to 30° C. It is also possibleto add instead of the nanodispersion the corresponding nanodispersionprephase to the water phase of the end formulation. He nanodispersionprephase is added to the water phase with stirring and preferably at atemperature in the range of the respective oil/water phase inversiontemperature (PIT).

[0175] In the case of solid end formulations it is advantageous to admixthe dehydrated form of the nanodispersion to the solid substancemixture.

[0176] The cosmetic end formulation is preferably used for the treatmentand protection of skin, mucosae or hair and, very particularly, assunscreen or as an after-sun preparation.

[0177] The nanodispersions used according to this invention can also beused as transport vehicles for oil-soluble dyes.

[0178] In another of its aspects, this invention thus relates to the useof the nanodispersion defined in claim 1 as carrier system foroil-soluble dyes.

[0179] Suitable dyes are of synthetic or also of natural origin and arecomposed from all known chromophores, for example azo, azoic,anthraquinone, caratenoid, quinoline, xanthene, diarylmethane,triarylmethane, stilbene, indigoid, phtalocyanine, nitro dyes as well asall other known chromophores, such as are also listed in Colour Indexunder CI 11000 to CI 77999.

[0180] Of these dyes, those are particularly interesting which are atleast partially soluble in organic media such as oils. This includes,for example, those dyes which are called solvent dyes or disperse dyes,the disperse dyes also including the group of the unloaded, directlyabsorbing hair dyes, for example derivatives of nitrobenzene or ofnitrodiphenylamine.

[0181] Examples of solvent dyes which may be used in accordance withthis invention are:

[0182] Solvent Black 3 (Cas-No.: 4197-25-5); Solvent Black 5 (Cas-No.:11099-03-9); Solvent Blue 35 (Cas-No.: 12769-17-4); Solvent Green 3;Solvent Green 7 (Cas-No.: 6358-69-6); Solvent Orange 1 (Cas-No.:2051-85-6); Solvent Red 24 (Cas-No.: 85-83-6); Solvent Red 43 (Cas-No.:15086-94-9); Solvent Red 48 (Cas-No.: 13473-26-2); Solvent Red 49:1(Cas-No.: 6373-07-5); Solvent Red 72 (Cas-No.: 596-03-2); Solvent Yellow44 (CAS No.: 2478-20-8); Solvent Yellow 18 (CAS No.: 6407-76-9).

[0183] Examples of disperse dyes which may be used in accordance withthis invention are:

[0184] Disperse Black 9 (CAS No.: 12222-60-4); Disperse Blue 1 (CASNos.: 2475-45-8); Disperse Blue 3 (CAS No.: 2475-46-9); Disperse Brown 1(CAS No.: 23355-64-8); Disperse Orange 3 (CAS No.: 730-40-5); thecompound of formula

[0185] ; Disperse Violet 1 (CAS-No.: 128-95-0); Disperse Violet 4(CAS-No.:1220-94-6); the compound of formula

[0186] examples of (unloaded) directly absorbing hair dyes are:

[0187] HC Blue No. 2 (CAS-No.: 33229-34-4); HC Blue No. 4 (reactionproduct of N-methyl-1,4-diaminoanthraquinone, epichlorohydrin andmonoethanolamine); HC Blue No. 5 (CAS-No.: 68478-64-8); the compound offormula

[0188] HC Blue No. 7 (Cas-No.: 90817-34-8); HC Blue No. 8 (Cas-No.:22366-99-0); HC Blue No. 9 (Cas-No.: 114087-42-2); HC Blue No. 10(Cas-No.: 102767-27-1); HC Blue No. 11 (Cas-No.: 23920-15-2); HC BlueNo. 12 (Cas-No.: 132885-85-9); the compound of formula

[0189] HC Blue No.14 (Cas-No.: 99788-75-7); HC Orange No. 1 (Cas-No.:54381-08-7); , HC Orange No. 2 (Cas-No.: 85765-48-6), HC Orange No. 3(Cas-No.:81612-54-6); the compound of formula

[0190] HC Red No. 1 (Cas-No.: 2784-89-6); HC Red No. 3 (Cas-No.:2871-01-4); HC Red No. 7 (Cas-No.: 24905-87-1); HC Red No. 8 (Cas-No.:13556-29-1); HC Red No. 9 (Cas-No.:56330-88-2); HC Red No. 10 (Cas-No.:95576-89-9);, HC Red No. 11 (Cas-No.: 95576-92-4), HC Red No. 13(Cas-No.: 94158-13-1); the compound of formula

[0191] HC Violet No. 1 (Cas-No.: 82576-75-8); the compound of formula

[0192] HC Yellow No. 2 (Cas-No.: 4926-55-0); HC Yellow No. 4 (Cas-No.:59820-43-8); HC Yellow No. 5 (Cas-No.: 56932-44-6); HC Yellow No. 6(Cas-No.: 104335-00-6); the compound of formula

[0193] HC Yellow No. 8 (Cas-No.: 66612-11 -1); HC Yellow No. 9 (Cas-No.:86419-69-4); HC Yellow No.10 (Cas-No.: 109023-83-8); HC Yellow No. 11(Cas-no.: 73388-54-2); HC Yellow No. 12 (Cas-No.: 59320-13-7); HC YellowNo. 13 (Cas-No.: 10442-83-8); the compound of formula

[0194] HC compound of formula

[0195] the compound of formula

[0196] HC Brown No. 1 (Cas-No.: 83803-98-9); HC Brown No. 2 (Cas-No.:83803-99-0); HC Green No. 1 (Cas-No.: 52136-25-1).

[0197] The nanodispersions used according to this invention can have thefollowing functions:

[0198] being carriers for allowing dyes to penetrate through certainpotential walls into media such as skin, hair or nails;

[0199] protecting the dyes from other ingredients of a formulation (orvice versa, protecting the formulation from another dyes), for examplein order to eliminate incompatibilities between formulation and solid.The dye is then separated in the core of the nanodispersion from theremainder of the formulation. Thus it is possible to prevent chainreactions with other ingredients which reactions are photo-initiated bythe dye;

[0200] introducing dyes which are only soluble in oil phases intoaqueous systems and stabilising them. The dye is then dissolved in thecore of the nanodispersion (oil phase) and the nanodispersion particleis in turn dispersed in the aqueous phase.

[0201] In the following Examples, percentages are by weight. Unlessotherwise stated, amounts of compounds used are based on the puresubstance.

Working Examples for Nanodispersion Prephases EXAMPLE 1 Miglyol 812Nanodispersion Prephase

[0202] soybean lecithin 17.30% polysorbate 80 34.00% miglyol 812 34.50%ethanol 14.20%

[0203] Preparation: Miglyol 812 and polysorbate 80 are mixed. Thesoybean lecithin is dissolved in ethanol and added to this mixture,resulting in a homogeneous clear liquid.

EXAMPLE 2 Miglyol 812 Nanodispersion Prephase

[0204] soybean lecithin 17.30% oleth-20 34.00% miglyol 812 34.50%ethanol 14.20%

[0205] Preparation: Miglyol 812 and oleth-20 are mixed, with heating.The soybean lecithin is dissolved in ethanol and added to this mixture,resulting in a homogeneous clear liquid.

EXAMPLE 3 Miglyol 812 Nanodispersion Prephase

[0206] soybean lecithin 17.30% laneth-20 34.00% miglyol 812 34.50%ethanol 14.20%

[0207] Preparation: Miglyol 812 and Laneth-20 are mixed, with heating.The soybean lecithin is dissolved in ethanol and added to this mixture,resulting in a homogeneous clear liquid.

EXAMPLE 4 Miglyol 812 Nanodispersion Prephase

[0208] soybean lecithin 17.30% vitamin E polyethylene glycol succinate34.00% (vitamin E TPGS, Eastman) miglyol 812 34.50% ethanol 14.20%

[0209] Preparation: Miglyol 812 and vitamin E polyethylene glycolsuccinates are mixed, with heating. The soybean lecithin is dissolved inethanol and added to this mixture, resulting in a homogeneous clearliquid.

EXAMPLE 5 Vitamin E Acetate Nanodispersion Prephase

[0210] soybean lecithin  9.00% polysorbate 80 34.00% vitamin E acetate36.60% miglyol 812 13.00% ethanol  7.40%

[0211] Preparation: Miglyol 812, vitamin E acetate and polysorbate 80are mixed. The soybean lecithin is dissolved in ethanol and added tothis mixture, resulting in a homogeneous clear liquid.

EXAMPLE 6 Parsol MCX/parsol 5000 Nanodispersion Prephase

[0212] soybean lecithin  5.00% polysorbate 80 34.00% parsol MCX 25.90%(octyl methoxycinnamate) parsol 5000 11.10% (4-methylbenzylidenecamphor) miglyol 812 13.00% ethanol 11.00%

[0213] Preparation: Parsol 5000 is dissolved in Parsol MXC and mixedwith miglyol 812 and polysorbate 80. The soybean lecithin is dissolvedin ethanol and added to this mixture, resulting in a homogeneous clearliquid.

Working Examples for Nanodispersions EXAMPLE 7 Miglyol 812Nanodispersion

[0214] soybean lecithin  1.73% polysorbate 80  3.40% miglyol 812  3.45%ethanol  1.42% aqua purificata ad 100.00%

[0215] Preparation: The water phase (e.g. 90 kg) is placed, withstirring (e.g. magnetic agitator), in a vessel at 50° C. The liquidnanodispersion prephase of Example 1 (e.g. 10 kg) is added to the waterphase with stirring (e.g. using a magnetic agitator).

EXAMPLE 8 Miglyol 812 Nanodispersion

[0216] soybean lecithin  1.73% oleth-20  3.40% miglyol 812  3.45%ethanol  1.42% aqua purificata ad 100.00%

[0217] The preparation is carried out in analogy to the procedure ofExample 7.

EXAMPLE 9 Migylol 812 Nanodispersion

[0218] soybean lecithin  1.73% laneth-20  3.40% miglyol 812  3.45%ethanol  1.42% aqua purificata ad 100.00%

[0219] The nanodispersion is prepared in analogy to the procedure ofExample 7.

EXAMPLE 10 Miglyol 812 Nanodispersion

[0220] soybean lecithin  1.73% vitamin E polyethylene glycol succinate 3.40% (vitamin E TPGS, Eastman) miglyol 812  3.45% ethanol  1.42% aquapurificata ad 100.00%

[0221] The nanodispersion is prepared in analogy to the procedure ofExample 7.

EXAMPLE 11 Dexpanthenol Nanodispersion

[0222] dexpanthenol 5.00% soybean lecithin 1.73% polysorbate 80 3.40%miglyol 812 3.45% ethanol 1.42% aqua purificata ad 100.00%

[0223] Preparation: The water phase containing dexpanthenol (e.g. 90 kg)is placed, with stirring (e.g. magnetic agitator), at 50° C. in avessel. The liquid nanodispersion prephase of Example 1 (e.g. 10 kg) isadded to the water phase with stirring (e.g. by means of a magneticagitator).

EXAMPLE 12 Vitamin E Acetate Nanodispersion

[0224] vitamin E acetate 2.00% soybean lecithin 0.49% polysorbate 801.86% miglyol 812 0.71% ethanol 0.63% aqua purificata ad 100.00%

[0225] Preparation: The water phase (e.g. 94.54 kg) is placed, withstirring (e.g. magnetic agitator), at 50° C. in a vessel. The liquidnanodispersion prephase of Example 5 (e.g. 5.46 kg) is added to thewater phase with stirring (e.g. by means of a magnetic agitator).

EXAMPLE 13 Parsol MCX/parsol 5000 Nanodispersion

[0226] parsol MCX 2.59% (octyl methoxycinnamate) Parsol 5000 1.11%(4-methylbenzylidene camphor) miglyol 812 1.30% soybean lecithin 0.50%polysorbate 80 3.40% ethanol 1.10% aqua purificata ad 100.00%

[0227] The nanodispersion is prepared in analogy to the procedure orExample 7.

[0228] Particle sizes and particles size distribution are compiled inthe following Table. TABLE 1 Particle Standard Particle diameter¹deviation size Nanodispersion [nm] [nm] distribution migylol 812nanodispersion 13.8 4.1 Gauss Example 7 dexpanthenol nanodispersion 19.75.4 Gauss Example 11 vitamin E acetate nanodispersion 12.2 5.5 GaussExample 12 parsol MCX / parsol 5000 14.6 5.2 Gauss nanodispersionExample 13

Dexpanthenol Nanodispersion (Example 11)

[0229] TABLE 2 Storage conditions Standard Duration TemperatureDiameter² deviation Dexpanthenol³ [months] [° C.] pH [nm] [nm] content[%] 0 6.1 19.7 5.4 5.37 3  7 6.1 19.0 6.7 5.36 25 6.1 22.2 7.7 5.32 406.3 36.6 14.2 5.23 6  7 6.1 20.8 7.3 5.30 25 6.2 24.1 9.2 5.26 40 6.435.4 17.7 5.20

Vitamin E Acetate Nanodispersion (Example 12)

[0230] TABLE 3 Storage conditions Standard Vitamin E DurationTemperature Diameter² deviation acetate [months] [° C.] pH [nm] [%]content [%]⁵ 0 6.1 12.2 5.5 2.04 3  7 6.1 16.1 6.6 2.02 25 6.1 17.5 7.02.04 40 6.0 15.4 6.8 2.01 6  7 6.1 17.0 6.9 2.04 25 6.0 17.6 7.2 2.03 406.0 20.8 7.9 2.02

Working Example for Cosmetic End Formulations with NanodispersionsEXAMPLE 14 O/W Treatment Lotion

[0231] polyglycerol methyl glucose distearate 2.00% capric/capryltriglyceride 6.50% mineral oil 6.50% glycerol 3.00% nanodispersion ofExample 12 5.00% carbomer 0.20% alcohol 10.00% phenoxyethanol + methyl-,ethyl-, propyl-, butylparabene 0.30% perfume 0.30% sodium hydroxide(45%) 0.09% water ad 100.00%

EXAMPLE 15 Day Cream with UV Protection (O/W)

[0232] PEG-5 glycerol stearate 5.0% steareth-21 2.0% mineral oil 30.0%cetyl alcohol 2.0% microcrystalline wax 1.0% propylene glycol 6.0%nanodispersion of Example 13 10.0% phenoxyethanol + methyl-, ethyl-,propyl-, butylparabene 0.3% water ad 100.0%

EXAMPLE 16 Liquid Syndet Having Fat-restoring Properties

[0233] fatty alcohol ether sulfate 7.5% fat restoring agent 3.0% pearlluster 2.0% thickener 1.0% nanodispersion of Example 10 5.0% perfume0.3% water ad 100.0%

EXAMPLE 17 Foam Bath Having Treatment Properties

[0234] sodium lauryl ether sulfate 9.0% coconut fatty aciddiethanolamide 2.0% polyglycol fatty acid ester (3EO) 3.0% perfume 1.0%nanodispersion of Example 7 4.0% preservative, citric acid, sodiumchloride, water ad 100.0%

EXAMPLE 18 Soothing O/W Lotion

[0235] stearic acid 1.50% sorbitan monostearate 1.00% sorbitanmonooleate 1.00% mineral oil 7.00% cetyl palmitate 1.00%polymethylsiloxane 1.50% glycerol 2.00% 1.2-propylene glycol 2.00%nanodispersion of Example 11 3.00% polyacrylic acid 0.15% sodiumhydroxide 0.30% perfume 0.50% preservative, water ad 100.00%

EXAMPLE 19 Skin Protecting W/O Lotion

[0236] glycerol sorbitan fatty acid ester 2.0% polyethoxy fatty acidester 2.0% isopropylisostearate 5.0% mineral oil 7.0% isopropylpalmitate4.0% wheat germ oil 3.0% propylene glycol 3.8% nanodispersion of Example12 5.0% MgSO₄ × 7H20 0.7% perfume 0.5% perservative, water ad 100.0%

EXAMPLE 20 Make-up Cream

[0237] glycerol monostearate 4.0% cetyl alcohol 1.0% stearic acid 2.0%mineral oil 4.5% cetylstearyloctanoate 5.0% octylpalmitate 3.0% talcum4.0% titanium dioxide 1.5% iron oxide 0.8% propylene glycol 5.0%polyethoxysorbitan monolaurate 1.0% xanthane 0.4%magnesium-aluminium-silicate 0.3% glycerol 5.0% nanodispersion ofExample 13 5.0% preservative, water ad 100.0%

EXAMPLE 21 Dexpanthenol Controlled Dosage Spray

[0238] phenoxyethanol 0.5% nanodispersion of Example 11 ad 100.0%

What is claimed is:
 1. A method of preparing a cosmetic end formulationusing a nanodispersion, which comprises (a) a membrane-forming molecule,(b) a coemulsifier and (c) a lipophilic component, by (α) mixing thecomponents (a), (b) and (c) until a homogeneous clear liquid is obtained(so-called nanodispersion prephase), and (β) adding the liquid obtainedin step (α) to the water phase of the cosmetic end formulations, steps(α) and (β) being are carried out without any additional supply ofenergy.
 2. Method according to claim 1, which is characterised in thatstep (α) is carried out in anhydrous medium.
 3. Method according toclaim 1, which is characterised in that step (β) is carried out withouthomogenisation.
 4. Method according to claim 1, which is characterisedin that the particles in the nanodispersion have an average diameter of<50 nm.
 5. Method according to claim 1, which is characterised in thatthe nanodispersion comprises, (a) as membrane-forming molecules,substances which are suitable for forming so-called bilayers, (b) ascoemulsifiers, substances which preferably form O/W structures and, (c)as lipophilic component, a functional lipophilic active agentcustomarily used in cosmetics.
 6. Method according to claim 1, which ischaracterised in that the nanodispersion comprises as component (a) aphospholipid, a hydrated or partially hydrated phospholipid, alysophospholipid, a ceramide or mixtures thereof.
 7. Method according toclaim 6, which is characterised in that component (a) is present in thenanodispersion in a concentration of 0.1 to 30% by weight, based on thetotal weight of the components (a), (b) and (c).
 8. Method according toclaim 1, which is characterised in that the nanodispersion comprises ascomponent (b) an emulsifier of the polyoxyethylene type, saturated andunsaturated C₈-C₁₈alkylsulfates, the alkali metal, ammonium or aminesalts of C₈-C₂₀fatty acids, C₈-C₂₀alkanesulfonates, fatty alcoholphosphorates, the salts of colic acid, invert soaps (quats); partialfatty acid esters of sorbitan, sugar esters of fatty acids, fatty acidpartial glycerides, alkylmaltoside, alkylglucosides, C₈-C₁₈betaines,C₈-C₁₈sulfobetaines or C₈-C₂₄alkylamido-C₁-C₄-alkylenebetaines,proteins, polyglycerol esters of fatty acids, propylene glycol esters offatty acids, lactates of fatty acids or a mixture of these substances.9. Method according to claim 8, which is characterised in that thenanodispersion comprises as component (b) at least on emulsifier of thepolyoxyethylene type.
 10. Method according to claim 1, which ischaracterised in that the nanodispersion comprises as component (b) anemulsifier of the polyoxyethylene type or a mixture of these substances.11. Method according to claim 10, which is characterised in thatcomponent (b) in the nanodispersion is polyethoxylated sorbitan fattyacid esters, polyethoxylated fatty alcohols, polyethoxylated fattyacids, polyethoxylated vitamin E derivatives, polyethoxylated lanolinand the derivatives thereof, polyethoxylated fatty acid partialglycerides, polyethoxylated alkylphenols, sulfuric acid semiesters,polyethoxylated fatty alcohols and the salts thereof, polyethoxylatedfatty amines and fatty acid amides, polyethoxylated carbohydrates, blockpolymers of ethylene oxide and propylene oxide.
 12. Method according toclaim 1, which is characterised in that component (b) in thenanodispersion used according to this invention is present in aconcentration of 1 to 50% by weight, based on the total weight of thecomponents (a), (b) and (c).
 13. Method according to claim 1, which ischaracterised in that the nanodispersion comprises as component (c) anatural or synthetic or partially synthetic di- or triglyceride, amineral oil, silicone oil, wax, fatty alcohol, guerbet alcohol or theester thereof, a lipophilic functional cosmetic active agent, includingsunscreens, or a mixture of these substances.
 14. Method according toclaim 13, which is characterised in that the nanodispersion comprises ascomponent (c) a sunscreen or a fat-soluble vitamin.
 15. Method accordingto claim 1, which is characterised in that component (c) is present inthe cosmetic end formulation in a concentration of 0.1 to 80% by weight.16. Method according to claim 1, which is characterised in that thenanodispersion comprises as component (d) a C₂-C₈alcohol.
 17. Methodaccording to claim 1, which is characterised in that the nanodispersionis present in the end formulation in a concentration of 0.01 to 99% byweight.
 18. Method according to claim 1, which is characterised in thatat least one component (a), (b) or (c) is an ingredient used incosmetics for treating or protecting the skin, mucosae and hair.
 19. Acosmetic end formulation in the form of a gel, which comprises ananodispersion as defined in claim
 1. 20. A cosmetic end formulation inthe form of a cream, lotion or milk, which comprises a nanodispersion asdefined in claim
 1. 21. A cosmetic end formulation in the form of astick, which comprises a nanodispersion as defined in claim
 1. 22. Acosmetic end formulation in the form of a spray or aerosol, whichcomprises a nanodispersion as defined in claim
 1. 23. A cosmetic endformulation in the form of a foam, which comprises a nanodispersion asdefined in claim
 1. 24. A cosmetic end formulation in the form of apaste, which comprises a nanodispersion as defined in claim
 1. 25. Acosmetic end formulation according to claim 19, wherein thenanodispersion is present in the aqueous phase.
 26. A cosmetic endformulation according to claim 19, wherein the aqueous phase comprisesthe nanodispersion in a concentration of 0.01 to 20% by weight.
 27. Acosmetic end formulation in the form of a powder, lacquer, pellet ormake-up, which comprises a nanodispersion as defined in claim 1, thenanodispersion being present in dehydrated form.
 28. A nanodispersionprephase, which is obtained by mixing the components (a)membrane-forming molecule, (b) coemulsifier, (c) lipophilic componentand, optionally, (d) a C₂-C₈alcohol until a homogeneous clear liquid isobtained, mixing being carried out in anhydrous medium.
 29. Ananodispersion prephase according to claim 28, which is characterised inthat mixing is carried out without any additional supply of energy. 30.A cosmetic end formulation in the form of an oil or lacquer, whichcomprises a nanodispersion prephase as defined in claim
 28. 31. Ananodispersion, which comprises (a) a membrane-forming molecule, (b) acoemulsifier and (c) a lipophilic component, which is obtained by (α)mixing the components (a), (b) and (c) until a homogeneous clear liquidis obtained, and (β) adding the liquid obtained in step (α) to the waterphase, steps (α) and (β) being carried out without any additional supplyof energy.